Modular floor system

ABSTRACT

A modular floor system comprises a plurality of modular floor elements, each of which can be individually lifted to and supported at preset heights to change the configuration of the floor. The modular floor elements can be placed, either individually or in groups, at different levels relative to each other, to form stages, stairs, seating areas, display areas, grandstands, and balconies. Each modular floor element substantially comprises a floor panel, a sliding post, a sliding post guide, and an air cylinder assembly. Each sliding post includes a low position stop pin located at the post&#39;&#39;s upper portion, a plurality of radially directed uniformly spaced positioning pin holes, a longitudinally directed keyway, and an air seal assembly located at the post&#39;&#39;s lower portion. The sliding post guide, which is rigidly set into a concrete slab, includes a key which interacts with the sliding post keyway, a pin support seat, and leveling means. The floor panel is fastened to the top of the sliding post, which, in turn, is vertically guided and laterally supported by the sliding post guide. The sliding post can be supported at any preset height by a positioning pin which is placed through a positioning hole on the sliding post. The positioning pin bears against the pin support seat located on the upper portion of the sliding post guide. The pin, in addition to the action of the combination comprising the key and keyway, also prevents rotation of the sliding post about its longitudinal axis by coacting with the pin support seat. The air cylinder assembly, which is fastened to the lower portion of the sliding post guide, is adapted to receive the sliding post and its air seal assembly. The sliding post is raised or lowered by introducing air pressure into the cylinder at a location below the lowermost position of the air seal assembly. The air supply system, which provides this air pressure, includes an orifice which, upon deactivation of the air system, allows air to controllably escape from the cylinder. This, of course, allows the sliding post to drop until the positioning pin rests upon the guide&#39;&#39;s pin support seat. Alternatively, the air cylinder and air seal assemblies can be deleted, in which case the sliding post can be raised or lowered by an overhead hoist or by a portable lift device located below the sliding post.

United States Patent [1 1 Fisher et al.

[ 51 Nov. 11, 1975 1 1 MODULAR FLOOR SYSTEM [76] Inventors: JulesFisher, 255 W. 19th St., New

York, N.Y. 10011; Olaf Soot, 9

Tomahawk Lane, Greenwich, Conn. 06830 [22] Filed: June 22, 1973 [21]Appl. No.: 372,752

[52] 1.1.5. Cl. 52/126; 52/7, 52/29; 52/115 [51] Int. Cl. E04B 5/43;B6613 9/04 [58] Field of Search 52/126, 7, 111, 122, 114, 52/29, 115;248/354 H, 354 P [56] References Cited UNITED STATES PATENTS 1,563,78212/1925 Partington 52/7 1,616,198 2/1927 Partington 52/7 2,687,2688/1954 Hawes 248/354 S 2,920,725 l/1960 Emmons 52/118 3,367,632 2/1968Vail 52/118 X 3,399,887 9/1968 Altier 52/7 X 3,495,370 2/1970 Habro eta1... 52/118 X 3,546,831 12/1970 Romo et al. 52/115 I FOREIGN PATENTS ORAPPLICATIONS 622,047 6/1961 ltaly 248/354 P 1,551,170 10/1968 France248/354 H 93,277 6/1923 Austria 52/7 128,627 l/l932 Austria 52/71,125,589 11/1956 France 248/354 P 1,030,040 5/1966 United Kingdom248/354 P 711,417 9/1931 France 248/352 Primary E.\'aminerEmest R.Purser Assistant E.\'aminerLeslie A. Braun Attorney, Agent, or Firm-ReneOliveras [57] ABSTRACT A modular floor system comprises a plurality ofmodular floor elements, each of which can be individually lifted to andsupported at preset heights to change the configuration of the floor.The modular floor elements can be placed, either individually or ingroups, at different levels relative to each other, to form stages,stairs, seating areas, display areas, grandstands, and balconies. Eachmodular floor element substantially comprises a floor panel, a slidingpost, a sliding post guide, and an air cylinder assembly. Eachslidingpost includes a low position stop pin located at the posts upperportion, a plurality of radially directed uniformly spaced positioningpin holes, a longitudinally directed keyway, and an air seal assemblylocated at the posts lower portion. The sliding post guide, which isrigidly set into a concrete slab, includes a key which interacts withthe sliding post keyway, a pin support seat, and leveling means. Thefloor panel is fastened to the top of the sliding post, which, in turn,is vertically guided and laterally supported by the sliding post guide.The sliding post can be supported at any preset height by a positioningpin which is placed through a positioning hole on the sliding post. Thepositioning pin bears against the pin support seat located on the upperportion of the sliding post guide. The pin, in addition to the action ofthe combination comprising the key and keyway, also prevents rotation ofthe sliding post about its longitudinal axis by coacting with the pinsupport seat. The air cylinder assembly, which is fastened to the lowerportion of the sliding post guide, is adapted to receive the slidingpost and its air seal assembly. The sliding post is raised or lowered byintroducing air pressure into the cylinder at a location below thelowermost position of the air seal assembly. The air supply system,which provides this air pressure, includes an orifice which, upondeactivation of the air system, allows air to controllably escape fromthe cylinder. This, of course, allows the sliding post to drop until thepositioning pin rests upon the guides pin support seat. Alternatively,the air cylinder and air seal assemblies can be deleted, in which casethe sliding post can be raised or lowered by an overhead hoist or by aportable lift device located below the sliding post.

2 Claims, 3 Drawing Figures US. Patent N0v.11, 1975 Sheet20f2 3,918,225

MODULAR FLOOR SYSTEM FIELD OF THE INVENTION- This invention relates to amodular floor system and, in particular, to such a system whose elementscan be individually lifted to and stably supported at predeterminedheights.

BACKGROUND OF THE INVENTION Stage and theater design techniques requireeconomy and flexibility of floor space. One approach to this problem isthe modular floor system concept. Prior Modular floor systems haverelied on conventional hydraulic, pneumatic, and mechanical liftingmachinery. These systems have been expensive and, consequently, theirconstruction has not been economically feasible. Some prior systems,especially those of the pneumatic type, have exhibited slow leaks andtherefore unstable height control.

Objects of the present invention are therefore to:

provide a modular floor system;

provide such a system of the pneumatic type which is not susceptible tounstable height control;

allow for a variety of seating and stage arrangements which suit thespecific requirements of a particular performance; and

provide for flexibility of space by using verticallyadjustable floorelements.

SUMMARY OF THE INVENTION According to the presentinvention, a modularfloor system comprises a plurality of modular floor elements, each ofwhich can be individually lifted to and supported at preset heights tochange the configuration of the floor. Each floor element substantiallycomprises a floor panel, a sliding post, a sliding post guide, and anair cylinder assembly. The floor panel is rigidly fastened to the upperportion of the sliding post and is perpendicular to the postslongitudinal axis. The floor panel incorporates anchors for mountingremovable seats, hand rails, fascias, and other components. A removablecover is provided on one side of the floor panel for ready access to thequick disconnect air coupling located'below on the concrete slab. Inaddition, the floor panel is removable and can be replaced by a varietyof structures, such as a turntable. These structures, of course, can befastened to the upper portion of the sliding post at any desired angularposition. Each sliding post includes a low position stop pin located atthe post's upper portion, a plurality of radially directed uniformlyspaced positioning pin holes, a longitudinally directed keyway, and anair seal assembly located at the posts lower portion. The positioningpin holes are located 90 from the keyway. The air seal assembly ismounted so as to permit a small amount of lateral motion. This, ofcourse, allows the air seal to center itself inside the air cylinder inorder to prevent binding. The sliding post guide, which is rigidly setinto the abovementioned concrete slab, includes; a key which interactswith the posts keyway to constrain the posts motion to the verticaldirection; a pin support seat; and leveling means. The sliding postguide provides lateral support to the sliding post when the sliding postis at a predetermined position or while it is being lifted or lowered.The pin support seat is also positioned 90 from the keyway. The slidingpost guide provides both vertical and rotational support to the slidingpost whenever the positioning pin rests on the pin support seat. Theleveling means allows for accurately controlling the vertical alignmentof the sliding post guide and there-. fore of the sliding post. Thelower portion of the sliding post guide is adapted for mounting the aircylinder assembly. The longitudinal axes of the sliding post guide, thesliding post,and the aircylinder assembly are concentric. The aircylinder assembly includes a relief valve and hose connections at thebottom portion thereof. The air supply utilized for lifting or loweringthe sliding post is connected to the air'cylinder by means of a quickdisconnect coupling and associated air hoses. The quick disconnectcoupling includes an orifice which allows air to escape from thecylinder via the orifice when the compressed air supply is disconnectedfrom the quick disconnect coupling. This, of course, allows for loweringof the sliding post until the positioning pin rests on the pin supportseat.

According to another embodiment of the present invention, an overheadhoist or other mechanical means such as a portable lifting devicelocated beneath the sliding post can be used to vertically raise thesliding post. In this embodiment, the air seal and cylinder assembliesare not required. The sliding post, floor panel, positioning pin, andsliding post guide interact substantially as before.

Features of the present invention are therefore that:

it utilizes a combination pneumatic-mechanical system for lifting andstably maintaining the floor panel at a predetermined height;

it utilizes a controlled air leak via an orifice to lowe the slidingpost until the positioning pin engages the pin support seat located onthe sliding post guide;

it utilizes a non-precision pneumatic lift system in conjunction with apositive mechanical support means;

the air supply meansis connected to the cylinder via a removable side"element located on the floor panel;

a positioning pin is "inserted into the sliding post to maintain thefloor'panel at a fixed predetermined height;

the sliding post guide maintains the vertical alignment of the slidingpost, prevents rotation of the sliding post, and supports the slidingpost via its pin support seat;

the sliding post and its associated guide are the only precisionelements of the system; and

only the sliding post guide must be accurately positioned and leveled.

Advantages of the present invention are therefore that:

it allows for economy and flexibility of theater and stage floor space;

it is adaptable for use with simple pneumatic lift means, a portablejack assembly, or an overhead hoist;

it is safe and economical;

the floor panel can be adapted to receive seats or other desiredstructures;

it is not susceptible to slow air leaks; and

field installation costs thereof are minimized.

BRIEF DESCRIPTION OF THE DRAWING Other objects, features, and advantagesof the present invention will be better appreciated by a considerationof the following detailed description and the 3 drawing in which:

FIG. I is a partially cross-sectional front view of a modular floorelement in the raised configuration according to the present invention;

FIG. 2 is an exploded perspective view of a modular floor element in theraised configuration and associated handrails, seats. lights andanchoring devices; and

FIG. 3 is a detailed cross-sectional view of an air seal assemblyaccording to the present invention.

DETAILED DESCRIPTION FIGS. 1 and 2 show a modular floor elementaccording to the present invention. Modular floor element 200substantially comprises floor panel assembly 10, sliding post assembly20, sliding post air seal assembly 30, sliding post guide assembly 40,air cylinder assembly 50, and quick disconnect coupling and air hoseassembly 60. Associated with modular floor element 200 are portablecompressed air supply with gun 70 and removable furnishings 100 mountedto floor panel assembly 10. A plurality of modular floor elements 200make up a modular floor system.

According to the present invention, floor panel assembly includes steelX-shaped frame 11 having associated therewith threaded studs 17 weldedto its underside, for rigidly and removably connecting floor panelassembly 10 to sliding post top plate 22. Flooring 12 and associatedside stiffening members 13 and toe guard 14 form a rigid panel, whichpanel is fastened on top of frame 11. Bumper strip 15 is fastened on allsides of the floor panel assembly at its top edge. Removable sideelement or plug 16 is placed into an opening at the side of the floorpanel assembly. The opening is used for connecting portable air gun 70into quick disconnect coupling 61 for raising or lowering sliding postassembly and associated panel assembly 10, when floor panel assembly 10and sliding post assembly 20 are at their lowest position. Flushanchoring devices with slotted key holes 117 are located at the end ofeach side of floor panel assembly 10. Anchoring sleeves 18, which areperpendicular to the top surface of floor panel assembly 10 and locatedat each corner thereof, are mounted within floor panel assembly 10.Anchoring sleeves 18 are furnished with cover plugs 19 for closing thesleeve openings when sleeves 18 are not used for anchoring furnishings100 to floor panel assembly l0.

Sliding post assembly 20 is used for raising and lowering floor panelassembly 10 and for supporting floor panel assembly 10 throughpositioning pin 27 on sliding post guide assembly 40 when floor panelassembly 10 is placed at any of its raised positions. Sliding postassembly 20 includes tubular member 21 having a circular cross sectionwhen viewed perpendicular to its longitudinal axis. Top plate 22 isrigidly welded or otherwise rigidly connected onto the extreme top endof tubular member 21 perpendicular to the longitudinal axis of suchtubular member. Top plate 22 is used for mounting floor panel assembly10 to the top end of sliding post assembly 20. Circular cap 26 is weldedor otherwise rigidly mounted onto the extreme bottom end of tubularmember 21, perpendicular to the longitudinal axis of such member.Circular cap 26 is used for pro viding support and connection forsliding post air seal assembly 30. Pin 23 is inserted through thetubular member near its top end and welded to the tubular member withboth its ends protruding through to the outside oftubular member 21.This pin is located at the longitudinal center-line of the tubularmember and per pcndicular to that center-line. in line with positioningpin holes 24. The purpose of pin 23 is to support sliding post assembly20 vertically on top of sliding post guide assembly 40, thereby bearingagainst groove 43, and to prevent its rotation relative to sliding postguide assembly 40, when floor panel assembly 10 and sliding postassembly 20 are at their extreme lowermost positions. Sliding postassembly 20 is vertically supported on top of sliding post guide 40 atany pre-set use position by removable positioning pin 27, which pin isinserted through positioning hole 24 which corresponds to the desiredelevation of floor panel assembly 10. Positioning pin 27 also preventsrotation of the sliding post assembly relative to sliding post guideassembly 40, when such pin is bearing on top of sliding post guideassembly 40 within groove 43.

Positioning holes 24 on sliding post tubular member 21 are drilledthrough both sides of tubular member 21 through the center-line thereofand at right angles to the longitudinal axis thereof. Positioning holes24 are spaced parallel to the longitudinal axis of tubular mem ber 21 soas to correspond to desired pre-set elevations of floor panel assembly10 use positions. The outside edges of positioning holes 24 are beveledso as to prevent distortion of the outside face of tubular member 21from possible impact forces resulting from positioning pin 27 hittingthe top of the sliding post guide assembly during the loweringoperation. Continuous keyway 25 is cut into one side of tubular member21, keyway 25 being parallel to the longitudinal axis of member 21. Inthis embodiment, keyway 25 is located at right angles to positioning pinholes 24; however, any other relative positioning of keyway 25 andpositioning pin holes 24 can be used. Keyway 25 is used to prevent therotation of sliding post assembly 20 relative to sliding post guide 40while sliding post assembly 20 is being raised or lowered and otherwisewhen it is notbeing supported by pin 23 or positioning pin 27. Keyway 25engages a key 42 which is part of sliding post guide assembly 40.

The functions of sliding post guide assembly 40 are as follows:

a. to rotationally and laterally guide and support sliding post andfloor panel assemblies 20 and 10, respectively;

. to vertically support. via pin 23, positioning pin 27,

or via compressed air in cylinder space 56, sliding post and floor panelassemblies 20 and 10, respectively;

c. to support air cylinder assembly 50;

to support the entire modular floor element on permanent structure ande. to provide simple means for positioning and leveling the entiremodular floor element relative to permanent structure 80 before rigidlyfastening it to the structure.

Sliding post guide assembly 40 includes east or welded metal cylindricalhousing 41, further including finished cylindrical guiding surfaces 46inside thereof, near its top and bottom ends; means for mounting key 42near its top end; and means for mounting air cylinder assembly 50 to itsbottom end. Cylindrical housing 41 further includes support flange orflanges 47 on the outside portion thereof and groove 43 for engaging andsupporting fixed pin 23 or removable positioning pin 27. The purpose ofcylindrical guiding surfaces 46 is to provide lateral support to slidingpost assembly 20 at any position, while in motion or while stationary.The purpose of groove 43 is to provide vertical support to sliding postassembly 20, through fixed pin 23 or through removable positioning pin27 when either of these pins bears against the surfaces of groove 43.Groove 43 also prevents rotation of sliding post assembly 20 and floorpanel assembly 10, when either pin 23 or 27 engages such groove.

Key 42 engages keyway '25 and rotationally guides sliding post assembly20 and floor panel assembly while they are in motion. Key 42 is fastenedto cylindrical housing 41 so as to permit its initial alignment withrelation to groove 43 during assembly. Key 42 is'accurately positionedwhen pin 27 bears against groove 43 so that the sides of keyway 25 arefree to slide in relation to key 42. After this alignment isaccomplished, key 42 connection is tightened to prevent movement thereofrelative to cylindrical housing 41. This alignment prevents possiblebinding, which can otherwise be caused by the jamming of keyway 25against key 42 whenever the alignment of either pin 23 or pin 27 togroove 43 is not precise. Sliding post guide assembly 40 is supportedduring installation by leveling bolts 45 and nuts 44. After it isproperly leveled and positioned, sliding post assembly 40 is rigidlygrouted in place with non-shrink grout 82. It is apparent that meansother than concrete slab 80 could be used for fastening sliding postguide assembly 40 to the permanent support structure.

Air cylinder assembly 50 includes tubular cylinder 51, bottom cap 53,pressure relief valve 54, and air pipe 55. The top end of air cylinderassembly 50 is fastened to the bottom end of sliding post guide assembly40, their longitudinal axes being concentric. Air cylinder assembly 50also includes pressure in cylinder space 56 whenever sliding postassembly overtravels in the upward direction. A compressed air source,not shown, and air gun 70 are connected to air cylinder assembly 50 viaquick disconnect coupling 61, by piping, and by flexible hose 60. Airgun 70 includes raising and lowering valves, not shown. Quick disconnectcoupling 6l, or its housing 63, includes a positioning device, notshown, which permits connecting air gun 70,to quick disconnect coupling61 only in one position. This is done so that the operators hand 71would be out of the way of floor panel assembly 10 as it travels upward.Quick disconnect coupling 61 further includes an orifice, not shown,which relieves the pressure in cylinder space 56 whenever air gun 70 isremoved from quick disconnect coupling 61. The controlled escape rate ofair from cylinder space 56 through this orifice slowly lowers slidingpost assembly 20 until either pin 27 or pin 23 engages groove 43 on topof sliding post guide assembly 40 thereby setting the height of floorpanel s sembly 10. The orifice in quick disconnect coupling 1&3guarantees that floor panel assembly 10 is always positively supportedby either positioning pin 27 or pin 23.

FIG. 3 shows air seal assembly 30 according to the present invention.Neoprene cup 31 is supported by retainer plate 32 and connected tocircular cap 26 through shoulder bolt 33, which bolt is rigidlyconnected or welded to circular cap 26. Retainer plate 32 and cup 31 arefree to move laterally within the limits of hole 36, which hole islarger than the diameter of bolt 33. This movement permits neoprene cup31 to align with air cylinder assembly 50 and eliminates binding in caseof minor misalignment between air cylinder assembly 50 and sliding postassembly 20. Circular bumper plate 34 is placed in between cap 26 andretainer plate 32 and held in place by shoulder bolt 33.

Bumper plate 34 prevents the bottom end of sliding post assembly 20 fromleaving sliding post guide assembly 40 in case of overtravel in theupward direction.

Circular neoprene ring 35 is placed on top of thebumper plate to absorbthe impact between bumper plate 34 and sliding post guide assembly 40during their contact.

Sliding post assembly 20 can be movedfrom sliding post guide assembly 40when bumper plate 34 is removed from the bottom of the sliding postassembly 20.

From H6. 1 it is apparent that each floor panel assembly can be raisedand set to any pre-set position. higher than its initial position, bygoing through the following steps:

a. remove plug 16;

b. insert air gun into quick disconnect coupling 61;

c. release pressured air by opening the valve, not shown, in air gun 70,into cylinder space 56, thereby lifting pin 27 off groove 43;

d. remove positioning pin 27;

e. raise sliding post assembly 20, together with floor panel assembly10, with compressed air, slightly above the desired elevation so thatthe corresponding positioning hole 24 is slightly above groove 43;

f. insert positioning pin 27 into the appropriate positioning hole;

g. release the compressed air from cylinder space 56 by using the valve,not shown, which is part of the air gun 70, or remove air gun 70 fromquick discon nect coupling 61. The escape of air from the cylinder space56 lowers sliding post assembly 20 until positioning pin 27 engagesgroove 43 and supports floor panel assembly 10 through sliding postassembly 20; and

h. replace the plug 16.

From HO. 1 it is apparent that each floor panel assembly can be loweredto any pre-set position lower than the initial position by going throughthe following steps:

a. remove plug 16;

b. insert air gun 70 into quick disconnect coupling c. releasepressurized air, by opening the valve, not shown, in air gun 70, intothe cylinder space 56, thereby lifting pin 27 off groove 43;

(1. remove positioning pin 27 and insert it into the appropriatepositioning holes above, corresponding to the desired new lowe'rpositionof floor panel assembly 10; and

e. release the compressed air from cylinder space 56 by the'use of thevalve, not shown, which is part of air gun 70, or remove air gun 70 fromquick disconr nect coupling 61. The escape of air from cylinder space 56lowers sliding post assembly 20 until positioning pin 27 engages groove43 and supports floor panel assembly 10 through sliding post assembly20.

It is further apparent from FIG. 1 that each floor panel assembly 10 ispositively supported by positioning pin 27 or pin 23 at any of itspositions which are preset by positioning pin holes 24. Therefore, thesemodular floor elements donot rely on air pressure to maintain theirpositions while in use. Also, no slow or accidental drift can occur,which is a common problem with pneumatic or hydraulic systems when notproperly maintained. Also individual floor elements can be placed andpositively supported at one or at various elevations, thereby providingthe means for changing the configuration of the floor to suit particularprogram requirements. In addition, each floor element can be used as atheatrical or display elevator for creating the desired visual orfunctional effects for a performance As an alternate, the portable airsource, not shown, air gun 70, quick disconnect coupling 61, housing 63,and piping 62 can be eliminated and replaced by permanent compressedair, a supply, piping, and appropriate control valves which would effectfunctions similar to those described above.

As a further alternate, the entire compressed air operating system canbe eliminated. This would include the deletion of sliding post air sealassembly 30; air cylinder assembly 50; quick disconnect coupling; airhose assembly 60; and portable compressed air supply with air gun 70.The compressed air lifting system can be replaced with a portable jackor lift engaging the bottom end of sliding post assembly 20, or by anoverhead hoist system connected to the topend of sliding post assembly20. The functions and details of all other compo- .nents of the modularfloor element described above would remain unchanged.

FIG. 2, in addition to the basiefloor element components describedabove, shows some of furnishings 100,

which can be used in conjunction with the modular floor elements. Seats105 are supported by legs 104 and held in position on top of floor panelassembly 10 by pins 103 inserted into anchoring sleeves 18. Light 101,can be inserted into anchoring sleeves l8. Guardrail units 102, orfascias, not shown, can be connected to the floor panel assembly throughanchoring devices 117. Many other furnishings, different floor panelshapes. turntables, or combined structures supported by one or moresliding post assemblies can be used in conjunction with the modularfloor system.

While the arrangement according to the present invention has beendescribed in terms of a specific embodiment, it will be apparent tothose skilled in theart that many modifications are possible within thespirit and scope of the disclosed principle.

What is claimed is:

1. In a modular floor system, a plurality of modular floor elements eachof which can be lifted to and re- .tained at a predetermined height andeach comprising:

8 guide means, first pin means fixedly attached to the posts upperexternal portion. and an air seal assembly located on the post's bottomportion, said first pin means being adapted to rest upon said 5 seatingmeans when said post is at its lowermost position;

a vertically directed hollow cylinder attached to the bottom portion ofsaid guide member and having one closed end and one open end, said postsair seal assembly being slidable along the interior portion of saidcylinder; and

means for supplying air to said cylinder, said cylinder includingorifice means for allowing air to controllably escape from saidcylinder;

activation of said supplying means causing said post to be verticallyraised relative to said guide member slightly above said predeterminedheight and said orifice means allowing said post to vertically drop tosaid predetermined height, second pin means being insertable into thehole corresponding to said predetermined height for resting on saidseating means thereby retaining said post at said predetermined height.

2. In a modular floor system, a plurality of modular floor elements eachof which can be lifted to and retained at a predetermined height andeach comprising:

a vertically directed hollow cylindrical guide member including seatingmeans on the upper portion thereof;

a hollow cylindrical post adapted to be vertically slidable along theinterior portion of said guide member, said post including a pluralityof uniformly spaced radially directed holes located along the postslength, first pin means fixedly attached to the posts upper externalportion, and an air seal assembly located on the post's bottom portion,said first pin means being adapted to rest upon said seating means whensaid post is at its lowermost position;

a vertically directed hollow cylinder attached to the bottom portion ofsaid guide member and having one closed end and one open end, said postsair seal assembly being slidable along the interior portion of saidcylinder; and

means for supplying air to said cylinder;

activation of said supplying means causing said post to be verticallyraised relative to said guide member slightly above said predeterminedheight and deactivation of said supplying means causing said post tovertically drop to said predetermined height, second pin means beinginsertable into the hole corresponding to said predetermined height forresting on said seating means thereby retaining said post at saidpredetermined height and means for allowing air to controllably escapefrom said cylinder.

1. In a modular floor system, a plurality of modular floor elements eachof which can be lifted to and retained at a predetermined height andeach comprising: a vertically directed hollow cylindrical guide memberincluding first vertical guide means, and seating means on the upperportion thereof; a hollow cylindrical post adapted to be verticallyslidable along the interior portion of said guide member, said postincluding second vertical guide means adapted to interact with saidfirst vertical guide means, a plurality of uniformly spaced radiallydirected holes located along the post''s length and 90* away from saidfirst and second vertical guide means, first pin means fixedly attachedto the post''s upper external portion, and an air seal assembly locatedon the post''s bottom portion, said first pin means being adapted torest upon said seating means when said post is at its lowermostposition; a vertically directed hollow cylinder attached to the bottomportion of said guide member and having one closed end and one open end,said post''s air seal assembly being slidable along the interior portionof said cylinder; and means for supplying air to said cylinder, saidcylinder including orifice means for allowing air to controllably escapefrom said cylinder; activation of said supplying means causing said postto be vertically raised relative to said guide member slightly abovesaid predetermined height and said orifice means allowing said post tovertically drop to said predetermined height, second pin means beinginsertable into the hole corresponding to said predetermined height forresting on said seating means thereby retaining said post at saidpredetermined height.
 2. In a modular floor system, a plurality ofmodular floor elements each of which can be lifted to and retained at apredetermined height and each comprising: a vertically directed hollowcylindrical guide member including seating means on the upper portionthereof; a hollow cylindrical post adapted to be vertically slidablealong the interior portion of said guide member, said post including aplurality of uniformly spaced radially directed holes located along thepost''s length, first pin means fixedly attached to the post''s upperexternal portion, and an air seal assembly located on the post''s bottomportion, said first pin means being adapted to rest upon said seatingmeans when said post is at its lowermost position; a vertically directedhollow cylinder attached to the boTtom portion of said guide member andhaving one closed end and one open end, said post''s air seal assemblybeing slidable along the interior portion of said cylinder; and meansfor supplying air to said cylinder; activation of said supplying meanscausing said post to be vertically raised relative to said guide memberslightly above said predetermined height and deactivation of saidsupplying means causing said post to vertically drop to saidpredetermined height, second pin means being insertable into the holecorresponding to said predetermined height for resting on said seatingmeans thereby retaining said post at said predetermined height and meansfor allowing air to controllably escape from said cylinder.